According to the report, onshore wind is the most cost competitive sources of not only renewable energy but also fossil-fuel based energy.
Note hydro is the only one that has a lower cost than wind in some cases, but it variability is high.
Source: IRENA report on Renewable Power Generation Cost in 2014. http://www.irena.org/menu/index.aspx?mnu=Subcat&PriMenuID=36&CatID=141&S....
More details at: http://cleantechnica.com/2015/01/19/new-report-confirms-renewable-power-...